ADB EURODIM TWIN TECH, Installation Manual

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EURODIM TWIN TECH
www.adblighting.com Installation manual - Page 54
Version 1.2
13. Appendix D: Specification of Magnetic Circuit Breakers (MCB)
In this chapter we would like to discuss the dimension and types of MCB used for our
dimmers. For 3 kW circuits ADB uses 13 A and for 5 kW circuits 20 A rated MCB with C
Curve. Below we will explain why we use these values; it has been carefully designed in our
product, for your maximum safety and protection.
Now following the laws we have all learned:
P(Watt) = U(Volts) x I(Amperes)
By applying this formula and a Voltage of 230 V you will receive 2.990W
3
(13 A) and 4.600 W
(20 A) maximum loads. At first sight this may be not sufficient
– be reassured this has been
well thought of and is fully intentional as we will explain.
ATTENTION: This formula may not be applied as simple as that because there is a second
factor to keep in mind and that is the curve of the selected line protection device. There are
many different curves MCB may have depending on the application (Motors, General
Household applications etc…)
“C” curve type protection is used exclusively for lighting applications. Below you can see the
graph depicting the current passing through the MCB. If you look carefully to the curve, you
will notice that the MCB will hold the factor of minimum 1.13 (maximum 1.45) for an infinite
amount of time.
The 13A nominative MCB will hold min. 14.69A (or 3.38kW) and the 20A nominative MCB
will hold min. 22.6A (or 5.2kW) over an infinite
amount of time.
ADB digital dimmers perform intelligent soft-starts
when flashing the circuit by the lighting console to
full. This clever programming algorithm of our
digital dimmers prevents the MCB from tripping and
helps you to save lamp life by inflicting less stress
on the lamp filament!
Attention: But one must never plug in cold tungsten
halogen loads in a dimmer (or even an undimmed
circuit) at 100% Full. Large tungsten filament lamps
may appear as short-circuit to any MCB exceeding
by far the short-circuit current of 10x nominative
value.
Result: the MCB will trip for sure!
Therefore always make sure that a dimmer circuit is
turned off, or at least at a very low value when hard-
plugging luminaires.
Additional Safety Features for extremely high short circuit values:
ADB exclusively features 63A HRC fuses protecting the modules against any internal short-
circuit and improving the ICC value of the cabinet to 50kA. This is an additional safety feature
may not be often found in competitor products.
3
All calculations are done with a supply current of nominative 230V in these examples.